The Last Contribution from the U.S. National Herbarium

1900 ◽  
Vol 34 (397) ◽  
pp. 74-75
Keyword(s):  
National Herbarium ◽  
The U.S

Candidates for neotypification of Blanco's names of Philippine plants: specimens in the U.S. National Herbarium

Taxon ◽  
2001 ◽  
Vol 50 (3) ◽  
pp. 947-954 ◽  
Author(s):  
Dan H. Nicolson ◽  
Dawn Arculus
Keyword(s):  
National Herbarium ◽  
The U.S

The transfer of types from the Escuela Agrícola Panamericana to the U.S. National Herbarium in 1956 by Louis O. Williams

Taxon ◽  
2009 ◽  
Vol 58 (3) ◽  
pp. 993-1001 ◽  
Author(s):  
Laurence J. Dorr ◽  
George E. Pilz ◽  
John Boggan
Keyword(s):  
National Herbarium ◽  
The U.S

Historical Introduction

1977 ◽  
Vol 35 ◽  
pp. 2-5
Author(s):  
R. D. Heidenreich
Keyword(s):  
Electron Emission ◽  
Secondary Electron ◽  
Secondary Electron Emission ◽  
50Th Anniversary ◽  
Secondary Emission ◽  
Wave Nature ◽  
Nobel Prize In Physics ◽  
Primary Electrons ◽  
The U.S ◽  
Mutual Agreement

This program has been organized by the EMSA to commensurate the 50th anniversary of the experimental verification of the wave nature of the electron. Davisson and Germer in the U.S. and Thomson and Reid in Britian accomplished this at about the same time. Their findings were published in Nature in 1927 by mutual agreement since their independent efforts had led to the same conclusion at about the same time. In 1937 Davisson and Thomson shared the Nobel Prize in physics for demonstrating the wave nature of the electron deduced in 1924 by Louis de Broglie.The Davisson experiments (1921-1927) were concerned with the angular distribution of secondary electron emission from nickel surfaces produced by 150 volt primary electrons. The motivation was the effect of secondary emission on the characteristics of vacuum tubes but significant deviations from the results expected for a corpuscular electron led to a diffraction interpretation suggested by Elasser in 1925.

Variations in Surface Textures of Quartz Sand using Electron Microscopy

1970 ◽  
Vol 28 ◽  
pp. 494-495
Author(s):  
Eugene J. Amaral
Keyword(s):  
Electron Microscopy ◽  
Glass Industry ◽  
Glass Slide ◽  
Distilled Water ◽  
Early Paleozoic ◽  
Secondary Effects ◽  
Surface Textures ◽  
High Silica ◽  
Sand Deposit ◽  
The U.S

Examination of sand grain surfaces from early Paleozoic sandstones by electron microscopy reveals a variety of secondary effects caused by rock-forming processes after final deposition of the sand. Detailed studies were conducted on both coarse (≥0.71mm) and fine (=0.25mm) fractions of St. Peter Sandstone, a widespread sand deposit underlying much of the U.S. Central Interior and used in the glass industry because of its remarkably high silica purity.The very friable sandstone was disaggregated and sieved to obtain the two size fractions, and then cleaned by boiling in HCl to remove any iron impurities and rinsed in distilled water. The sand grains were then partially embedded by sprinkling them onto a glass slide coated with a thin tacky layer of latex. Direct platinum shadowed carbon replicas were made of the exposed sand grain surfaces, and were separated by dissolution of the silica in HF acid.

The Effects of Estradiol on Chronically Damaged Human Fallopian Tubes: A SEM Study

1985 ◽  
Vol 43 ◽  
pp. 648-649
Author(s):  
A. Toledo ◽  
G. Stoelk ◽  
M. Yussman ◽  
R.P. Apkarian
Keyword(s):  
Menstrual Cycle ◽  
Epithelial Cell ◽  
Secretory Cell ◽  
Estrogen Therapy ◽  
Fallopian Tubes ◽  
Cell Surfaces ◽  
Proliferative Phase ◽  
Cyclic Patterns ◽  
Sem Study ◽  
The U.S

Today it is estimated that one of every three women in the U.S. will have problems achieving pregnancy. 20-30% of these women will have some form of oviductal problems as the etiology of their infertility. Chronically damaged oviducts present problems with loss of both ciliary and microvillar epithelial cell surfaces. Estradiol is known to influence cyclic patterns in secretory cell microvilli and tubal ciliogenesis, The purpose of this study was to assess whether estrogen therapy could stimulate ciliogenesis in chronically damaged human fallopian tubes.Tissues from large hydrosalpinges were obtained from six women undergoing tuboplastic repair while in the early proliferative phase of fheir menstrual cycle. In each case the damaged tissue was rinsed in heparinized Ringers-lactate and quartered.

Antitrust: U.S. Supreme Court Affirms FTC Jurisdiction but Vacates Scope of Analysis on CDA Policy

1999 ◽  
Vol 27 (2) ◽  
pp. 197-198
Author(s):  
Joseph R. Zakhary
Keyword(s):  
Public Relations ◽  
Supreme Court ◽  
Federal Trade Commission ◽  
Ninth Circuit ◽  
Court Of Appeals ◽  
For Profit ◽  
Rule Of Reason ◽  
Antitrust Analysis ◽  
Business Financing ◽  
The U.S

In California Dental Association v. FTC, 119 S. Ct. 1604 (1999), the U.S. Supreme Court reviewed a decision by the U.S. Court of Appeals for the Ninth Circuit that a nonprofit affiliation of dentists violated section 5 of the Federal Trade Commission Act (FTCA), 15 U.S.C.A. § 45 (1998), which prohibits unfair competition. The Court examined two issues: (1) the Federal Trade Commission's (FTC) jurisdiction over the California Dental Association (CDA); and (2) the proper scope of antitrust analysis. The Court unanimously held that CDA was subject to FTC's jurisdiction, but split 5-4 in its finding that the district court's use of abbreviated rule-of-reason analysis was inappropriate.CDA is a voluntary, nonprofit association of local dental societies. It boasts approximately 19,000 members, who constitute roughly threequarters of the dentists practicing in California. Although a nonprofit, CDA includes for-profit subsidiaries that financially benefit CDA members. CDA gives its members access to insurance and business financing, and lobbies and litigates on their behalf. Members also benefit from CDA marketing and public relations campaigns.

Life Beyond 1MeV

1980 ◽  
Vol 38 ◽  
pp. 30-33
Author(s):  
K.H. Westmacott
Keyword(s):  
Electron Microscopy ◽  
Past Experience ◽  
The Other ◽  
Good Case ◽  
Other Hand ◽  
The U.S

Life beyond 1MeV – like life after 40 – is not too different unless one takes advantage of past experience and is receptive to new opportunities. At first glance, the returns on performing electron microscopy at voltages greater than 1MeV diminish rather rapidly as the curves which describe the well-known advantages of HVEM often tend towards saturation. However, in a country with a significant HVEM capability, a good case can be made for investing in instruments with a range of maximum accelerating voltages. In this regard, the 1.5MeV KRATOS HVEM being installed in Berkeley will complement the other 650KeV, 1MeV, and 1.2MeV instruments currently operating in the U.S. One other consideration suggests that 1.5MeV is an optimum voltage machine – Its additional advantages may be purchased for not much more than a 1MeV instrument. On the other hand, the 3MeV HVEM's which seem to be operated at 2MeV maximum, are much more expensive.

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